1. Field of the Invention
This invention relates to a separable fastener which is provided with a multitude of hooking elements on a substrate cloth.
2. Description of the Prior Art
There have thus far been known face-contacting separable fasteners which consist of a male fastener component having a multitude of upright hooking elements on one side of a substrate cloth and a female fastener component having a multitude of loop elements distributed on a contacting side of its substrate cloth for disengageably engaging with the hooking elements on the male fastener component. In most cases, for forming the male or hooking fastener component, firstly loops are formed by using monofilaments as warps in the weaving process of the substrate cloth to obtain an elongated or broad male fastener strip. Then, in order to enhance the interlocking action of the male fastener component with the female fastener component, the loops are cut open by the so-called clipping method employing a cutter blade assembly which is provided with a fixed cutter blade between a couple of movable cutter blades, to form hooks which are each opened by a clipped space of a width corresponding to the thickness of the intermediate fixed cutter blade. Although many of known male fastener components are made by this method, it is the general practice to narrow the intervals of the individual hooks to increase the number of the hooks in the transverse or longitudinal direction of the fastener for the reason that a greater hook density will increase the chances of engagement between the hook and loop elements. As a matter of fact, a study on the currently available male fastener components could not find any article which had hook elements at intervals greater than about 1.6 mm.
However, the conventional male fastener strips have drawbacks that they are hard in texture and that the small pitch hook-forming cutter blades which are used in the manufacturing process are apt to be blocked with the loop fragments which are clipped off to form the void spaces in the hooks, resulting in failure in clipping the loops appropriately or in undesirably impaired appearance. In addition, the positions of the void spaces in the individual hooks are extremely deviated to one side in the longitudinal direction of the fastener.
Therefore, a male fastener component with such a construction has a problem that the coupling rate is varied depending upon the direction of engagement when the fastener is brought into face-to-face engagement with a female or loop fastener component, showing a different coupling strength depending upon the direction of engagement. It follows that, when such a separable fastener is attached as a joining or connecting member to articles of apparel, shoes, seat covers, or the like, it is necessary to pay attention to the fastener mounting direction--although discrimination of the fastener mounting directions is difficult in some cases. Particularly, it is unsuitable for application to shoes, gloves, diapers, belts or other articles which require a coupling force in one lateral direction. The fastener has another drawback that its stiffness is incongruous with an apparel or cloth of fine texture if used as a fastener therefor.